Table 11-1 identifies the minimum requirement for storing classified material. It must be used in evaluating the security container and supplemental control required to properly safeguard classified information stored within. STORAGE Top Secret material will be stowed in a class A or B vault, a strongroom that meets the prescribed standards, or a General Services Administration (GSA) approved security container. When located in a building, structural enclosure, or other areas not under U.S. Government control, the vault, strongroom or security container must be protected by an alarm system or guarded by U.S. citizens during nonoperating hours or located in an alarmed area that affords protection equal to or better than that prescribed. When an alarm is used, the physical barrier must be adequate to prevent the following actions: Surreptitious removal of the material Observation that would result in compromise of the material The physical barrier must be such that forcible attacks will result in evidence of attempted entry into the room or area. The alarm system must, at a minimum, provide immediate notice to a U.S. security force of an attempted entry. Secret and Confidential material will be stored in the manner prescribed for Top Secret material or until phased out; in a steel filing cabinet having a built-in GSA-approved combination lock; or as a last resort, a steel filing cabinet equipped with a steel lockbar, secured by an approved GSA combination padlock When a lockbar container is used, the following procedures apply: The keeper and staples of the lockbar must be secured to the filing cabinet by welding, rivets, or peened bolts. The drawers of the container must be held securely closed when the lockbar is in place, so their contents cannot be removed by forcing open a drawer. During working hours, padlocks must be placed in the cabinet or locked through the staple until the cabinet is secured at the end of the day. Table 11-1.—Storage Requirements SHORE INSTALLATIONS SHIPS AIRCRAFT TS¹ S C TS¹ S C TS¹ S C CLASS “A” VAULT X X X CLASS “B” VAULT X² X X STRONGROOM X³ X² X X⁵ X² X X⁵ X² X GSA CONTAINER X² X X X² X X X² X⁴ X LOCK BAR CABINET X² X⁴ X² X X² X⁴ LOCKED CONTAINER OF X⁶ X⁶ X⁶ X⁶ SUBSTANTIAL METAL OR WOODEN CONSTRUCTION 1 Must be located in buildings, ships, and aircraft that are under U.S. Government control; otherwise, must be protected by an alarm system or be guarded during non-working hours by U.S. citizens. 2 Surrounding area locked and access to area controlled by U.S. personnel. 3 Container alarmed or guarded by U.S. personnel. 4 Surrounding area locked. 5 Area alarmed and patrolled every hour by U.S. personnel. 6 Surrounding area locked when not manned by U.S. personnel. Locked area must be checked every 24 hours. 11-7